Sebi has come across serious anomalies and a huge number of possibly fictitious investors after analysing truck loads of documents submitted by Subrata Roy's Sahara group to substantiate its claim of over Rs 20,000-crore refunds.

To locate genuine investors who may have deposited money with Sahara group, the regulator also wants to issue public notices in regional language newspapers and through other avenues, especially in northern and eastern states of the country.

Sahara group, whose chief Subrata Roy was yesterday sent into judicial custody, had deposited Rs 5,120 crore with Sebi after court orders. It claims to have already refunded all but Rs 2,000 crore in cash directly to investors. The court had ordered refund of over Rs 24,000 crore in August 2012.

Sebi has contested Sahara's direct refund claims.

However, Sebi's analysis of documents submitted by Saharas has thrown up large-scale mismatch -- in dates on application forms and redemption vouchers, addresses, names, bond details, among others -- in these papers, sources said.

There are numerous instances of one person having hundreds of accounts, one account having multiple beneficiaries, one person with multiple address and one address having tens of individuals. There are some people whose claimed dues spread over multiple accounts run into crores of rupees.

Besides, there are thousands of cases where addresses are untraceable, as also cases having innocuous addresses like national highways, and just names of villages, towns or roads, sources said on condition of anonymity.

A large chunk of these details have also been presented before the Supreme Court through written and oral submissions, they said, while adding that there are also cases of payment dates being shown earlier than the voucher dates.

The months-long analysis, which was conducted with the help of hundreds of scanners, computers and a robotic system installed at a huge warehouse in suburbs of Mumbai by hundreds of people, began early last year soon after Saharas delivered more than 100 trucks full of cartons containing documents.

Sebi has finally managed to sort over three crore application forms of investors who were issued OFCDs (Optionally Fully Convertible Debentures), as per claims of Saharas, and close to 2.4 crore redemption vouchers through which the group claimed to have refunded the investors.

The physical documents were first scanned and then given distinctive numbers for easy-storage in the robotic system installed at SHCIL (Stock Holding Corporation of India Ltd) warehouse, which has been hired